A homeowner called the Extension office after noticing bees or yellow jackets were repeatedly visiting a small koi pond in the yard. What was going on? Well, insects, like all of us, need water too!
Many insects receive water from nectar or via their prey, but honeybees, bumblebees, wasps, and many other insects visit dewy leaves, mud puddles, bird baths, pools, pet water bowls, or even decorative koi ponds to refuel their H2O needs, especially in hot, dry weather. Bees can use water to regulate humidity in the hive and for evaporative cooling. Butterflies are often seen around mud puddles siphoning up water. Different species of wasps mix water and mud or wood pulp to build their nests. No doubt water is an important resource for insects beyond drinking! Recently we've had quite a few 90 degree days here in NE Ohio so it is not surprising that it appeared an entire hive had a conga-line to the koi pond and back to the nest. One resource sites that on the hottest days, bee foraging may halt in favor of workers collecting water.
A shallow water bowl or makeshift mud puddle may be a welcome addition to your pollinator gardens. But be careful, don't drown your beneficial predators and pollinators! Shallow bowls or bird baths with rocks, sand, or other landing pads (like lily pads) can help! To avoid mosquitos or other unwanted water-borne insects, change water frequently.
The homeowner noted that the insects did not bother anyone on the adjacent porch. They got a front row seat to some interesting, though not unusual behavior. This could be alarming if bees and wasps are coming near pools where kids are playing. In most cases, if left alone they will collect their water and be off. Unfortunately once a reliable water source is located it may be difficult to deter them from returning. Remember that both bees and wasps are BENEFICIAL insects. However, if you do find that there is more conflict between bees and your swimming area than is tolerable, the United States Department of Agriculture has a factsheet with some tips for managing bees around the pool.
- More information on bees and water needs can be found here from University of California and here from Texas A&M.